We’ve been with them for years and never had cause to complain. They even sorted out the OH’s stay in a UK hospital some years back without problems, just a phone call to make sure it was an illness and not an accident which would have been covered by his employer’s insurance, not CSS. Doctor/hospital, etc, bill them direct and then they send us their invoice for our share to be paid.
We also have CSS. I have had no complaints. I have called their customer service a few times and have always been able to find someone who speaks English. I was also happy with the MD I was set up to talk with for a phone consult the one time I needed this. My only complaint is that I am not crazy about the family practice we are designated to use, but I don't think CSS is to blame for this.
We were with CSS before, never had any problems. Now with SWICA due to employer discount for the additional covers, they have it all in English. But as said, CSS has always been fine and replying to questions in a decent time
I was with CSS for 5+ years, but now changed to Atupri. They're minimally cheaper, but offer a different model. It was introduced this year and is available for a pilot phase only on ZH, BErn, Lucerne.
With CSS, the cheapest was the Tel-Care model. With Atupri, I now have a model called "FlexCare". Wit hthis, i can go directly to some selected doctors without calling them up before.
In any case, it's definitely worth to compare the offers on Comparis.ch every year, just to know if you're still running on an optimal plan.